The present invention relates to a heat developing apparatus and its control method for providing an image of appropriate density at all times.
According to the prior art, the heat developing apparatus used for heat development of a light sensitive film for heat development containing a latent image formed thereon is used in various manners. Some heat developing apparatuses are equipped with multiple film loading sections for use as a large-capacity tray for reducing the frequency of film supply, and others are designed to permit selection from different-sized films (14 inxc3x9717 in or 11 inxc3x9714 in) or to permit selection from films of the same size having different base densities. Further, in the heat developing apparatus, the sensitivity of the film may vary according to the lot when loaded with a new film package. Therefore, the first sheet is exposed and developed on a tentative basis according to a predetermined exposure pattern. Then the density is measured, the difference from a desired density is fed back to the process system, and the obtained density is maintained at a constant level in the step of so-called calibration. Density correction is performed for the subsequent heat development, thereby providing an image of appropriate density in some cases, according to the prior art. However, especially the heat-processable photo-sensitive material has relatively large variations of sensitivities according to the lot. So special emphasis is placed on this calibration step.
The distribution of temperature in the apparatus may undergo temporary change when the cover or the like is released to load the film on the main unit side of the heat developing apparatus, or power supply to the major portion of the equipment may be shut off for the purpose of ensuring electric safety when the door is opened. In the exposure system using acousto-optic modulation (AOM) means in this case, the characteristics of the AOM driver circuit as well as the temperature in the exposure section may undergo changes. Further, if the light sensitive film for heat development is left in the apparatus for a long time, the sensitivity is known to change and the sensitivity is found to deteriorate. If the temperature inside the apparatus is high, sensitivity tends to deteriorate easily in some cases. As a result, in some of the prior art heat developing apparatuses, calibration is automatically performed immediately when the door is closed after the tray has run out of film and the door has been opened to load a new film package.
However, when the film immediately after having been loaded does not sufficiently conform to the temperature in the apparatus, and the exposure system and the AOM system in particular is easily subjected to the temperature characteristics of the driver. If calibration is performed under these conditions, correction has not been conducted adequately in some cases. Further, for example, when the upper and lower trays are used as the aforementioned large-capacity tray after calibration, the film of the upper tray is used automatically if the lower tray runs out of film. During the time, a new film is loaded into the lower tray and calibration is performed. Actually, there is time before the film on the lower tray is used, and calibration data becomes invalid in some cases under the influence of the temperature history in the apparatus during this time, according to the prior art.
In view of the aforementioned problems involved in the prior art, it is an object of the present invention to provide a heat developing apparatus and its control method that eliminates the adverse effect of the variations in temperature inside the apparatus upon the development density and ensures an image of appropriate density at all times.
To achieve the aforementioned object, the first heat developing apparatus of the present invention comprises:
supply means (unit) having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means (unit) for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means (developing unit) for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means (a device) for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means (controller) for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, when the aforementioned image signal is received and a print request is received after a new package incorporating the aforementioned heat-processable photo-sensitive material has been loaded on the aforementioned loading section.
This first heat developing apparatus provides correction by control means when the apparatus has received a print request, not immediately after a new package including the heat-processable photo-sensitive material has been loaded. So the heat-processable photo-sensitive material can be exposed and developed after it has been corrected for density at the temperature inside the apparatus immediately before exposure and development of the heat-processable photo-sensitive material. This properly eliminates impact upon development density of the variation of sensitivity of the heat-processable photo-sensitive material due to changes of temperature in the apparatus and characteristic changes of exposure means, thereby ensuring an image of appropriate density at all times.
The second heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density if the aforementioned image signals have already been received when a new package incorporating the aforementioned heat-processable photo-sensitive material is loaded on the aforementioned loading section.
This second heat developing apparatus provides correction by control means when multiple signals are input to the apparatus and the system is waiting for printing, not immediately after a new package including the heat-processable photo-sensitive material has been loaded. So the heat-processable photo-sensitive material can be exposed and developed after it has been corrected for density at the temperature inside the apparatus immediately before exposure and development of the heat-processable photo-sensitive material. This properly eliminates impact upon development density of the variation of sensitivity of the heat-processable photo-sensitive material due to changes of temperature in the apparatus and characteristic changes of exposure means, thereby ensuring an image of appropriate density at all times.
The third heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, a predetermined time after a new package incorporating the aforementioned heat-processable photo-sensitive material has been loaded on the aforementioned loading section.
This third heat developing apparatus provides correction by control means after the lapse of a predetermined time, not immediately after a new package including the heat-processable photo-sensitive material has been loaded. This permits the heat-processable photo-sensitive material to be exposed and developed after the heat-processable photo-sensitive material in the package has been corrected for density when it has sufficiently conformed to the temperature inside the apparatus and the exposure means and developing means have reached the steady state characterized by few characteristic changes. This properly eliminates impact upon development density of the variation of sensitivity of the heat-processable photo-sensitive material due to changes of temperature in the apparatus and characteristic changes of exposure means, thereby ensuring an image of appropriate density at all times. In this case, it is possible, for example, to make arrangements in such a way that the control means is equipped with a timer where a predetermined time is set, and the timer operates upon loading of a new package.
The fourth heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, a predetermined time after the aforementioned heat developing apparatus has become ready state, after a new package incorporating the aforementioned heat-processable photo-sensitive material has been loaded on the aforementioned loading section.
This fourth heat developing apparatus provides correction by control means a predetermined time after the apparatus gets ready for printing, not immediately after a new package including the heat-processable photo-sensitive material has been loaded. This permits the heat-processable photo-sensitive material to be exposed and developed after the heat-processable photo-sensitive material in the package has been corrected for density when it has sufficiently conformed to the temperature inside the apparatus and the exposure means and developing means have reached the steady state characterized by few characteristic changes. This properly eliminates impact upon development density of the variation of sensitivity of the heat-processable photo-sensitive material due to changes of temperature in the apparatus and characteristic changes of exposure means, thereby ensuring an image of appropriate density at all times. In this case, it is possible, for example, to make arrangements in such a way that the control means is equipped with a timer where a predetermined time is set, and the timer operates when the apparatus becomes ready.
In the third or fourth heat developing apparatus, the aforementioned exposure means comprises either or both of the acousto-optic modulation driver and high frequency superposing section, and the aforementioned predetermined time can be set based on either or both of the temperature characteristics of the aforementioned acousto-optic modulation driver and the temperature characteristics of the aforementioned high frequency superposing section. This allows the correction to be performed by the control means after the lapse of a predetermined time when the temperature characteristics of the aforementioned acousto-optic modulation driver and the temperature characteristics of the aforementioned high frequency superposing section have reached the steady state. Thus, validity of the correction for the density thereof is maintained on a stable basis, and an image of appropriate density can be supplied at all times.
The fifth heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, when the aforementioned developing means has reached a predetermined temperature history after a new package incorporating the aforementioned heat-processable photo-sensitive material has been loaded on the aforementioned loading section.
This fifth heat developing apparatus provides correction by control means when the developing means as a major heat source in the apparatus has reached a predetermined temperature history, not immediately after a new package including the heat-processable photo-sensitive material has been loaded. This permits the heat-processable photo-sensitive material to be exposed and developed after it has been corrected for density when the temperature in the apparatus has reached the steady state. This properly eliminates impact upon development density of the variation of sensitivity of the heat-processable photo-sensitive material due to changes of temperature in the apparatus and characteristic changes of exposure means, thereby ensuring an image of appropriate density at all times.
In the fifth heat developing apparatus, a temporary change in the distribution of temperature in the apparatus is caused by opening of the door of the heat developing apparatus, for example, when a new package is loaded. Further, electric supply to the major portion of the apparatus is cut off for the sake of ensuring electrical safety at the time of opening the door, resulting in a temporary reduction of the temperature of the developing means. The developing means goes back to the predetermined temperature after the door has been closed, and correction is started by the control means after the lapse of a predetermined time. This arrangement properly eliminates the influence of the characteristic changes of the developing means resulting from reduced temperature, thereby ensuring density correction to be performed.
Further, the aforementioned heat developing apparatus comprises multiple aforementioned loading sections. As a result, when a new package is loaded into one of the loading sections during the use of the apparatus, density correction can be performed at properly timed intervals under the conditions of the aforementioned first to fifth heat development apparatuses, while the heat development material is supplied from another loading section, without the heat development material of this new package being corrected by the control means immediately.
The sixth heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein the next correction is performed a predetermined time after a correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density.
In the sixth heat developing apparatus, correction is again performed by the control means after the lapse of a predetermined time. This arrangement allows density correction to be performed at properly timed intervals, in response to changes in sensitivity of the heat-processable photo-sensitive material and characteristic change of the exposure means due to the influence of the changes in the temperature inside the apparatus resulting from the passage of a predetermined time, thereby supplying an image of appropriate density at all times.
The seventh heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein, after correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, the density value of the aforementioned heat-processable photo-sensitive material is read by the means for obtaining the aforementioned density information, and the density value read is compared with the reference (standard) density value, and the aforementioned next correction is performed if a predetermined variation in density has occurred.
In the seventh heat developing apparatus, correction is performed again by the control means if a predetermined level is exceeded by the variation of density obtained by comparison between the density value obtained from the heat-processable photo-sensitive material where the normal image is developed during the use of the apparatus and the reference density. Despite changes in the sensitivity of the heat-processable photo-sensitive material and characteristic changes of the exposure means under the influence of temperature changes in the apparatus as well as changes in the development density, this arrangement ensures density correction to be performed at properly timed intervals, thereby providing an image of appropriate density at all times. In this case, the reference value can be a predetermined density or the density measured in the previous correction by the control means.
Further, the eighth heat developing apparatus of the present invention comprises:
supply means having multiple loading sections for loading a heat-processable photo-sensitive material,
exposure means for forming a latent image on the aforementioned heat-processable photo-sensitive material fed by the aforementioned supply means in response to an image signal or a predetermined signal for measuring density,
development means for heat development of a heat-processable photo-sensitive material containing the aforementioned latent image,
means for gaining information on the density of the aforementioned developed heat-processable photo-sensitive material, and
control means for controlling either or both of the aforementioned exposure means and the aforementioned developing means in such a way that the difference from a desired density is corrected based on the aforementioned density information;
wherein correction is performed by the aforementioned control means based on the aforementioned density information obtained by forming and developing a latent image in response to the predetermined signal for measuring the aforementioned density, a predetermined time after the development by the aforementioned developing means.
In the eighth heat developing apparatus, correction is again performed, a predetermined time after the previous development by developing means. In response to changes in the sensitivity of the heat-processable photo-sensitive material and characteristic changes of the exposure means due to the passage of the predetermined time, this arrangement ensures density correction to be performed at properly timed intervals, thereby providing an image of appropriate density at all times.
According to the eighth heat developing apparatus, when the power supplied of the heat developing apparatus is turned off for a long time, for example, on non-business day or the like, the time from the previous development is measured by a timer or the like, and power supply is turned on again to permit control to be performed by the control means after the lapse of a predetermined time. This arrangement allows density correction to be performed at properly timed intervals even if the apparatus is not used for a comparatively long time.
The aforementioned sixth to eighth heat development apparatuses allow correction to be performed by the control means when a new package incorporating the heat-processable photo-sensitive material has been loaded. Then it allows correction to be made again by the control means under the aforementioned conditions. The number of the loading section of the sixth to eighth heat developing apparatuses may be one or more than one.
Correction by the control means in the aforementioned first to eighth heat developing apparatuses can be performed by changing either or both of the amount of light of the aforementioned exposure means and temperature in development by the aforementioned developing means. This arrangement allows the development density of heat-processable photo-sensitive material to be changed to a desired density.
In the aforementioned first to eighth heat developing apparatuses, the aforementioned loading section is loaded with a package incorporating the aforementioned heat-processable photo-sensitive material and indicating the characteristic information on the heat-processable photo-sensitive material. So the aforementioned characteristic information is read, and either or both of the amount of light of the aforementioned exposure means and development temperature of the aforementioned development means is preferably set based on the characteristic information read in this manner. This arrangement allows the amount of light of the exposure means and development temperature to be set, based on the characteristic information, even if the characteristics of the heat-processable photo-sensitive material are different for each lot, so variations of density due to variations of characteristics for each lot can be corrected. This arrangement ensures correction of density at the time of correction by the control means, and supplies an image of appropriate density at all times.
The control method of a heat developing apparatus according to the present invention comprises;
a step of feeding a heat-processable photo-sensitive material,
a step of forming a latent image by exposure on the heat-processable photo-sensitive material based on the image signal, and
a step of heat-developing the heat-processable photo-sensitive material with the aforementioned latent image formed thereon.
The aforementioned control method is characterized by further comprising;
a step of loading the package incorporating the aforementioned heat-processable photo-sensitive material into the aforementioned heat developing apparatus,
a step of determining if the density of the heat-processable photo-sensitive material in the aforementioned package is to be corrected or not,
a step of exposing and forming a latent image on the aforementioned heat-processable photo-sensitive material in response to a predetermined signal for density measurement when the aforementioned density is to be corrected,
a step of heat-developing the heat-processable photo-sensitive material containing the aforementioned latent image,
a step of obtaining the information on the density of the image for measuring the density of the aforementioned developed heat-processable photo-sensitive material, and
a step of correcting the aforementioned density so as to correct the difference from the desired density based the information on the density of the image for measuring the density.
According to this heat developing apparatus control method, the proper time for density correction is determined before it is performed. This arrangement ensures density correction to be performed at properly timed intervals, without density correction uniformly performed immediately before a package has been loaded into the heat developing apparatus. This arrangement properly eliminates the influence upon the development density by the changes in the sensitivity of the heat-processable photo-sensitive material and characteristic changes of the exposure means under the influence of temperature changes in the apparatus, and provides an image of appropriate density at all times.
The aforementioned density correction according to the heat developing apparatus control method is preferably performed in any one of the following cases;
when an image signal is received and there is a print request;
when the apparatus has received multiple image signals and is waiting for printing;
when a predetermined time has passed after loading of the aforementioned package;
when a predetermined time has passed after the apparatus got into the ready state; and
when the temperature inside the apparatus has reached a predetermined temperature history.
It is preferred to include the step of determining if re-correction is to be performed or not after the aforementioned density correction. This re-correction is preferably performed in one of the following cases;
a predetermined time after the previous density correction, when a certain fluctuation of density occurs after the density of the heat-processable photo-sensitive material having been developed subsequent to the previous density correction is read, and this reading is compared with the reference density, and a predetermined time after the previous development.